Rotating mechanism for percussive tools



Nov. 13 ,1923. V

1,474,338 E. G. GARTIN ROTATING AMECHANISM FR PERCUSSIVE TOOLS Filed Dec. 20. 1919 Iv ven 127'.' E571 6. v6&7? a. l by ity Patented Nov. 13, 1923.

UNITED STATES vPa'rlszNr oFFglcs.

ELMER G'. GARTIN, 0F CLAREMONT, NEW HAMPSHIRE, ASSIGNOR T0 SULLIVAN MA- CHINERY COMPANY, A CORPORATION F IVIASSAGHUSETTSH 1 ROTATING IVIECHANISM FOR PERCUSSIVE TOLS.

Application filed December 20, 1919.

To all 'whom t may concern.'

Be it known that I, ELMEI: AGr. GAn'rrN,

a citizen ot' the United States, residing at Claremont, in the county ot Sullivan and State of New Hampshire, have invented certain new and useful Improvements in Rotating Mechanism for Percussive Tools, of which the following is a '.t'ull, clear, and exact specification.

My invention relates to rotating mecha nism for percussive tools.

. It has for its object to provide an improved form of rotation device, and one which is simple in construction and of great strength. A further object of my invention is to provide an improved rotation device of the character set forth which is especially adapted to use in a hammer drill.

In the accompanying drawings I have shown, for purposes ot illustration, one embodiment which my invention may assume in practice.

Fig. 1 represents a longitudinal section through a percussive tool embodying the illustrative embodiment of my invention, certain parts which do not directly pertain thereto being omitted'.

Fig. 2 is a transverse section on lme 2-2 30 of Fig. 1.

Fig. 3 is a transverse section on line 3 3 of Fig. 1.

In this illustrative embodiment, the cylinder 1 of the percussive tool has its ends closed 5 by front and rear heads 2 and 3 respectivelya and in the cylinder there reciprocates a. piston 4 under control of a valve mechanism 5 which is of well known construction.

As a means to impart to the piston an oscillating movement simultaneous with its reciprocation, I have provided a riie bar rigidly secured with respect to the rear head 3, and preferably formed integral therewith. The rifle bar 10 is provided with alternate spiral tongues 12 and grooves 13 cooperatinowith grooves 14 and tongues 15 formed in a bushing 16 ixedly secured in the rear end of the piston, the piston being bore-d out as shown at 17 to receive the ,rifle bar when the piston is moving upon its backy ward stroke. As a result of this construction a point in the periphery of my piston partakes of both a reciprocatory and an oscillatory motion.

To transmit this oscillatory motion to a Serial N o. 346,414.

mechanism whereby it may be transpov into a unit-directional, intermittent nw" of rotation, I provide the piston with a forwardly extending reduced portion 20 adapted to pass through a circular opening 21 in the front head2 and iorm upon this piston extension a series of straight tongues 22 and grooves 23. Located in a suitable chuck housing member 25, which is secured to the front head 2, is a chuck member 26 having a squared socket 27 for a. tool 2S. In an 'enlarged rearwardly extending portion 30 of the chuck there is formed a housing 31 for a pawl carrier 32 and to cooperate with usual pawls 33 the inner peripheral wall of the housing 31 is provided with a series o1' racket teeth 34. Between the portion of the chuck and the front head 2 of the cylinder I provide a racket collar 36 adapted to transmit the thrust o the chuck to the front head 2. The ratchet collar 'surrounds a reduced portion of the pawl carrier and the latter is provided with a central opening in the periphery of which a series of straight grooves 37, with intervening tongues 38, are formed, these being adapted to receive and cooperate with the tongues 22 and grooves 23 of the piston extension 20. As a result of this construction, the pawl carrier 32 partakes of the osdillation imparted to the piston by the rifle bar.

The operation of this mechanism is as follows: Assuming the piston 4 to be in the position indicated and moving upon its forward stroke, it will obviously receive a right hand or clockwise partial rotation due to the action of the tongues 12, 15 and grooves 14, 13. As the forward extension 2O of the piston, by its straight tongues 22 and grooves 23 cooperates with the straight grooves 37 and tongues 38 formed in the pawl carrier 32, the latter will be partially rotated in the same direction as the piston, and by the engagement ofthe pawls33 with the ratchet teeth 34 will cause a partial ro-v tation of the chuck. Attention is directed to the fact that upon the backward movement of the pistou, its direction or' rotation Y will be reversed, and the pawl carrier willv llt) or rifle bar.

lVhile I have in-this application specifically described one form which my invention may assume in practice, `it will be understood that this form ofthe same is shown vfor purposes of illustration and that the inventionmay be modified and embodied in other forms without departing from its spirit or the scope of the appendedclaims.

What Iclaim as new and desire to secure .by Letters Patent is:

l. In a percussive tool comprising a cylinder anda percussive piston, a tool actuated by said piston, means to impart an .osclllatingmotion to said piston comprising a .fixed rifle barvcooperating with said piston, land means to transforinsaid oscillating motion to an intermittent .rotary motion and impartthe.latterto the tool.

2.111 a .permissive tool, a cylinder, a percussive piston, a rotary' chuck, an oscillating member therein, .driving l connection between said member and said chuck, 4saidpercuss'ive piston having a` straight tongue and groove connection with the oscillating member for oscillating it, andmeans to cause the piston .to partake of an alternate partial rotation in opposite directions comprising a spiral .tongue and groove ,connection be- ;tweenfa fixed portion of said cylinder and said piston. t

3. In a percussive tool, a cylinder, a percussive piston, a rotary chuck, an oscillating member, a ratchet and pawl connection between the chuck andv member, a straight tongue and groove connection between the percussive `piston and the oscillating member for oscillating the latter, and means causing the piston to (partially rotate. in opposite directions on alternate strokes comprislng '.atiXed bar having ,a spiral tongue 'and orooveconnection with the piston.

pawlcarrierhaving astraight tongue and vgroove connection. with said percussive `piston wherebyrotative movement of the` piston maybe transmitted to the pawl carrier, land a: xedriie bar having spiral-tongue i. and groove connection with said piston to ycanse alternate oscillations .thereof in opposite/'directions. Y

.In testimony whereof I aiX my signature.

ELMER e. GrtRTiN. 

